1. Field of the Invention
The invention relates to a mechanically driven device for cleaning the oral cavity, in particular an electric toothbrush, and to an accessories mount for a device of this type.
2. Discussion of the Prior Art
Electric toothbrushes generally comprise a handpiece, in which the electric drive means are accommodated, a brush head and a spindle which connects the handpiece to the brush head.
An electric toothbrush of this generic type is known from European reference EP 0 850 602, which was filed,in the name of the present applicant. This toothbrush essentially comprises a handpiece, a brush head, a pin which connects the handpiece to the brush head and a motor which is arranged in the handpiece and sets an unbalanced mass in rotation. The unbalanced mass is arranged in the vicinity of the brush head and is set in rotation by an elongate pin which is coupled to the output spindle of the drive motor. The housing part which bears the drive means is attached to the handpiece via damping means in order to prevent vibrations in the handpiece. During use, the rotary movement of the unbalanced mass generates a centrifugal force which in turn, in the brush head, generates vibrations which are damped in the handpiece.
This device comprises a brush which is arranged at the end of the brush head in order to clean the oral cavity. Although the way in which it functions is satisfactory, the used brushes cannot be replaced since they remain fixedly connected to the device.
Toothbrushes are already known from the prior art. According to some proposals, the brushes are removably attached to the end of the brush head, while according to other proposals they are connected to a mount which is arranged removably on the pin which connects the brush to the drive mechanism. In both cases, there are sealing problems, since the water and toothpaste can penetrate into the interior of the device; for design reasons, the attachment parts are connected to drive parts of the toothbrush which are arranged in the interior. In addition, only the brush is exchanged, while its mount remains attached to the device, and for this reason hygiene requirements are no longer satisfied if it is intended for the device to be used by another person as well.
Therefore, one object of the invention is to eliminate the above-mentioned drawbacks and to provide an electric toothbrush which is fitted with an accessories mount, in which the used brushes can be replaced easily and in which the required hygiene conditions are satisfied in the event of use by different people.
Another object of the invention is to provide an accessories mount for electric toothbrushes to which different accessories for cleaning the oral cavity can be removably and therefore exchangeably attached.
A further object of the invention is to provide an accessories mount of simple structure for electric toothbrushes, which is easy to fit to the device and to remove again from the device, which functions reliably and which can be manufactured as a mass-produced item at the lowest possible price.
According to the invention, these objects are achieved by means of an accessories mount for electric toothbrushes which is equipped with a motor arranged in the handpiece for driving the means which generate the vibrations in the brush head. The means which generate the vibrations are arranged in the interior of an elongate protective cover which is attached to the handpiece. The accessories mount comprises a sleeve which is fitted onto the protective cover and covers the latter over at least part of its length.
The means which generate the vibrations in the brush head, in particular the unbalanced mass and the spindle which sets the unbalanced mass in rotation, are arranged in the interior of the elongate protective cover, one end of which is fixedly connected to the handpiece of the device and the other end of which is arranged freely. The protective cover is designed as a closed part for sealing reasons. In addition, the accessories which are provided for cleaning the oral cavity are held by an accessories mount which is substantially formed by a sleeve surrounding the protective cover.
This has the advantage that all the components of the vibration mechanism are arranged in a hidden and encapsulated position and therefore do not come into contact with the fingers of the user. A protective cover of this type made from plastic also provides additional protection for people who are sensitive to metal. In addition, this solution ensures that there is a good seal against water and toothpaste, since the protective cover is designed as a closed part.
Another advantage is that each user has his own accessories mount, the length of the sleeve corresponding to the length of introduction into the oral cavity. As a result of the user changing the sleeve, at the same time the accessory is changed and therefore the outer surface of the protective cover which supports the sleeve remains clean.
The sleeve advantageously covers the protective cover over its entire length which projects beyond the handpiece.
The protective cover is thus protected by the appropriate sleeve which has been fitted during use over its entire length and is not exposed to contamination by cleaning liquid flowing along the sleeve.
The bottom end of the protective sleeve is advantageously connected to the handpiece by means of an elastic ring.
In an electric toothbrush as described in EP 0 805 602 which has been filed in the name of the applicant, the unbalanced mass is advantageously arranged in the vicinity of the brush head. The unbalanced mass is advantageously set in rotation by an elongate spindle, and the driving force of the motor is transmitted to the spindle via a flexible coupling arranged in the vicinity of the brush head. The fact that the rotation point is at a distance from the load point, in particular from the center of gravity of the unbalanced mass, increases the amplitude of the vibrations. The elastic ring which connects the end of the protective cover to the handpiece ensures that the vibrations are magnified in the brush head and are attenuated in the handpiece.
Preferably, the sleeve at its one end has attachment means for releasable attachment to the protective sleeve and, at its other, opposite end, has holding means for the accessories provided for cleaning the oral cavity.
The means for attaching and locking the sleeve on the protective cover are provided at a distance from the region which receives the toothpaste, so that the toothpaste cannot contaminate the locking mechanism and no functional problems occur.
The end of the sleeve which bears the accessories is advantageously oriented obliquely with respect to the longitudinal axis of the sleeve.
This configuration offers the advantage that the brush can be passed to the mouth in an ergonomic way, depending on the way it is handled by the user, but the mechanism accommodated in the protective cover remains aligned in a straight position. In addition, this obliquely oriented configuration exhibits good mechanical strength.
The angle between the end region of the sleeve and its longitudinal axis is advantageously between 8xc2x0 and 20xc2x0, preferably 15xc2x0. It has been found that an optimum ergonomic design is achieved with an angle of inclination of this magnitude.
The means for holding the accessories are advantageously formed by a part which has an opening for receiving the accessories.
It is thus possible to insert various types of exchangeable accessories which have pegs with a suitable cross-sectional shape into the mount, with the accessories, in the most simple design in particular, being pressed into the receiving opening. The clear width of the receiving opening is advantageously of polygonal, preferably square design.
This has the advantage of providing a simple and reliable holding and locking means, the peg of the accessory being clamped into the receiving opening.
The receiving opening is preferably of continuous design.
In this way, it is possible for the accessory to be attached to one side or the other of the accessories mount, as desired.
According to a preferred embodiment of the invention, the accessory is formed by an oval brush. A brush of this type can be guided to the teeth in such a way that its larger diameter is oriented either parallel or perpendicular to the row of teeth, depending on the intended purpose, in particular that of cleaning the teeth, massaging the gums, etc.
According to another embodiment of the invention, the accessory is formed by a rotary piece with a conical tip. Such an accessory can be used in conjunction with an accessories mount according to the invention, preferably for cleaning the interdental spaces and the gum line.
According to another embodiment of the invention, the accessory may be formed by dental floss which is secured in a holder.
It is also possible for a dental-floss holder to be fitted to an accessories mount according to the invention, in which case the dental floss is arranged in a fixed position in the holder but it is possible to exchange the dental-floss holder or to attach it in an inclined position on one or the other side of the accessories mount.
The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of the disclosure. For a better understanding of the invention, its operating advantages, and specific objects attained by its use, reference should be had to the drawing and descriptive matter in which there are illustrated and described preferred embodiments of the invention.